Control system.



H. L. BEACH.

CONTROL SYSTEM.

APPLICATION FILED SEPT. a. 1914.

1,244,459. Patented Oct. 30, 1917.

2 MW. F .WM. m FofleyE/V/ r/Jb 3 WITNESSES: mvamon Howard L. Beach.

. I Envy/ref M09 22 20 UNITED STATES PATENT OFFICE.

HOWARD I1. BEACH, OF EDGEWOOD PARK, PENNSYLVANIA, ASSIGNOR T0 WESTING-HOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYL-VANIA.

CONTROL SYSTEM.

Specification of Letters Patent.

Application filed September 8, 1914. Serial No. 860,605.

Toiall whom it may concern:

Be it known that I, HOWARD L. BEACH, a citizenof the United States, anda resident of Edgewood Park, in the county of Allegheny and State ofPennsylvania, have invented a new and useful Improvement in ControlSystems, of which the following is a specification.

My invention relates to systems of control for electric motors, and ithas special reference to the control of electric motors that are adaptedfor use in propelling electric railway vehicles and the like.

One object of my invention is to simplify, and reduce the cost ofconstruction and maintenance of control systems of the aboveindicatedcharacter.

Another object of my invention is to increase the flexibility andefliciency of operation of systems of the general type underconsideration. I

In many types of control systems for electric railway vehiclesthatemploy auxiliary control circuits for electrically governing aplurality of power-operated, particularly fluid-pressure operated,switches, it is customary practice to control the operation of theswitches directly from the auxiliary control circuit through asuitablemaster con troller. In the case of automatic systems, inaddition to the apparatus mentioned, it is necessary to provide anaccelerating relay or limit switch, which is set to operate upon thetraversal therethrough of a predetermined current value, and also amultiplicity of electricalinterlocking contact members that areassociated with corresponding control fingers and are actuated by therespective switches to energize the magnet coils of the switches, inaccordance with a predetermined sequence, to effect automaticprogressive operation of the several motor-controlling switches.

Disadvantages of this type of control system are the inflexibility ofoperation, inasmuch as all of the switches which are dependent upon theaccelerating relay must operate at the same current value, and the firstcost and maintenance of the large number of interlocking contactmembers: It is, therefore, with the purpose of obviating thesedisadvantages that my invention is designed.

According to my invention, I reduce to a necessary minimum the. numberof switches that are governed directly from the auxiliary controlcircuit and also the number of electrical interlocking contact membersthat are carried by the switches; and to effect automatic acceleration,I provide a pluralityof adjustable electro-magnetic devices which areconnected in series-circuit relation with the motors and aremechanically actuated by the switch that closes, just prior in thesequence, to efi'ect fluid-pressure operation of the respective switcheswhen the current decreases to a predetermined value. In this way, theuse of a separate accelerating relay or limit switch is obviated andeach switching device may be adjusted to close at the proper and mostefficient time and at the most suitable individual current value,irrespective of the conditions which determine the operation of anyother switch.

In the accompanying drawing, Figure 1 is a diagrammatic view of the maincircuits of a system of control embodying my invention; Fig. 2 is adiagrammatic view of the auxiliary control circuits that are adapted foroperating the motor controlling switches shown in Fig. 1 in accordancewith the sequence chart, Fig. 3, of well-known form; Fig. 4 is adiagrammatic view illustrating the general arrangement of the two typesof switching devices which are employed in the control system shown inFig. 1; and Fig. 5 is a sectional detail view of certain of theswitching devices illustrated in Fig. 4.

Reference may first be had to Fig. 5, which illustrates the preferredform of one type of switching device that is employed in the systemsshown in Figs. 1 and 4, the device showing, for example, the relation ofthe switch R11 to the electromagnetic device that is associated with theswitch R A stationary switch member 1 is supported in position in anysuitable and familiar manner (not shown), and a cooperating movablecontact member 1 is suitably insulated from, and is movable with, a rod2 to the lower end of which is secured a piston 3 which operates withina cylinder 4 in opposition to the action of a helical spring 5. Asuitable inlet pipe 6 is provided to admit fluid-pressure from anysuitable source (not shown). A pin 7 is secured near the free end of therod 2, for a purpose hereinafter specified. It will be understood thatany other suitable type of. fluid pressure-operated device may bemployed,

if desired. The electro-magnetic valve illustrated in the figurecomprises a suitable incasing member 11 which is provided with a caphaving a hollow raised central portion or hub 12; a coil 13 ofrelatively large current capacity which is disposed within the incasingmember 11 and which is adapted for connection in the main motorcircuits, as indicated in Fig. 1; a centrally disposed movable core 14which cooperates with a stationary longitudinally adjustable core 15 andis separated therefrom by a suitable air gap 16; a valve member 17 whichis suitably secured to the lower end of the core 14 and is biased by aspring member 18 to close an inlet passage or pipe 19 from the source offluid-pressure; an exhaust chamber 20 which is normally in communicationwith a passage or pipe 21 leading to the operat ing cylinder of thecorresponding switch; a second valve member 22 which is adapted to closecommunication between the chamber 20 and the passage 21 upon actuationof the electro-magnetic device; a rod 23 which is secured to the upperend of the core 14 and is movable therewith; a loose collar 24 which isdisposed near the upper end of the rod 23; a second collar 25 which isrigidly secured to an intermediate point of the rod 23; a helical spring26 which is supported upon the upper surface of the hub 12 and isadapted to bias the collar 24 and the rod 23 to their upper positions, asecond helical spring 27 which is disposed around the rod 23 between theinner flat surface of the hub 12 and the collar 25, and is adapted tobias the rod 23 and the associated valve member 17 to its lower position; a pin 28 which is secured to opposite sides of the collar 24 andextends through a longitudinally disposed slot 29 in the rod 23; and anoscillating rod or lever 30, one looped end 31 of which extends aroundthe rod 23 and rests upon the collar 24 and is pivoted at anintermediate point 32 to have its free end engaged by the pin 7 of therod 2, under predetermined conditions.

The electromagnetic action of the coil 13 tends to maintain the valve'17closed, and, therefore, the coil 13 and the upper spring 26 act inconjunction with each other and in common opposition to the action ofthe spring 27. With no current flowing, the action of the spring 26predominates over that of the spring 27, and the valve 17 remainsclosed; also, the electromagnetic force exerted by the coil 13, whilethe motor current traversing the coil is maintained above predeterminedvalue, is suflieient to overcome the action of the spring 27, eventhough the spring 26 be temporarily rendered inoperative upon the rod23, as hereinafter described. The current value at which the deviceoperates may be readily varied to suit the particular conditions and toobtain the most efficient operation by adjusting the position of thestationary core 15 relative to the movable core 14.

The operation of the device just described may be set forth as follows:Upon closure of the switch RR by the admission of fluidpressure to thecylinder 4, the pin 7 of the rod 2 engages the free end of the rod 30,and, consequently, depresses the other end 31 of the rod, causing thecoller 24 to be actuated downwardly, a movement which is permitted bythe pin and slot construction. The actuation of the spring 26 upon therod 23 and associated valve member 17 is thus relieved. However, so longas the motor current passing through the coil 13 remains above apredetermined value, the electromagnetic action of the coil issufficient to overcome the action of the spring 27, and no furtheroperation of the electromagnetic device occurs. When the current dropsbelow the predetermined value, however, the action of the spring 27becomes greater than the force exerted by the coil 13, and the valvemember 17 is actuated to its lower position to admit fluidpressure tothe coresponding cylinder, thereby closing the switch. The switch isthen maintained in its closed position, irrespective of furthervariations in the motor current, by the disposal of the coil 13 in acircuit which receives only a small portion of the motor current, or byopening the circuit of the coil 13, as hereinafter set forth.

The opening action of the device illustrated is effected as follows:Upon the opening of the switch with which the device is mechanicallyassociated, the pin 7 is disengaged fromthe free end of the rod 30,whereupon the spring 26 overcomes the action of the spring 27 andactuates the rod 23 and its associated valve member 17 to their upperpositions to permit of the release of fluid pressure from the operatingcylinder of the corresponding switch through the passage 21 and theexhaust chamber 20.

As indicated in Fig. 4, the switching device construction just describedapplies to the switches RIP, M R, RR and R, which are respectivelyadapted for the described actuation, by the switches JR or M, J or G,RR- R and RR". The other switches illustrated in Figs. 1 and 4, namely,JR, J, G, S and M are of a familiar fluidpressure type which areelectrically-governed from an auxiliary control circuit, and aresubstantially of the construction illustrated below the dotted line C-Cin the electromagnetic device R of Fig. 5; the magnet coil, of course,in this case comprising a relatively larger number of turns of finewire, since the coil is adapted for operation from a materially highervoltage. The fluid-pressure-operated piston and cylinder for theswitches referred to may be of any 1'30 shown in Figs. 1 and 4 asdirectly electromagnetically actuated.

' Referring. to Fig. 1, the system here shown is of a familiarseries-parallel type which employs bridging transition during theoperation of the motors from series tov parallel relation and comprisesa supply circuit conductor marked .Trollyl; a. return circuit conductormarked Ground; a plurality of electric motors respectively pro videdwith armatures A and A and field magnet windings F and F .a plurality ofmotor-controlling switches M M JR, J and G; a plurality of acceleratingresistors, one of which is adapted to be short-circuited by a switch Sand is employed during series operation only of the motors, and othersof which are adapted to be short-circuited by switches R R RR and RRrespectively, and a reversing switch RS, of familiar construction, whichis adapted to simultaneously reverse the electrical relations of thefield windings F and F with respect to. the corresponding armatures. Theassociation of the series-connected coils 13 with the correspondingswitches is indicatedby the respective arrows.

Reference may now be had to Fig. 2, in which the apparatus showncomprises, in addition to the actuating coils of the switches S, J, G, JR and M and the various electrically interlocking contact members whichare associated therewith, an auxiliary source of energy, such as astorage battery SB or any othersuitable means, a ,master controller MC,a master reverser MR and the auxiliary control circuits for the operation of the reversing switch RS.

The master reverser is adapted to assume an ofi,. a forward and areverse position, in accordance with customary practice; and the mastercontroller is adapted to assume a plurality of motor-operating positionsat, 7) and c. The system illustrated is entirely automatic, and,'if itis desired to opcrate the motors without interruption from starting tofull parallel relation, themaster controller may be .moved immediatelyto its final operating position a. If it is desired to operate themotors to full series relation only, this may be efl'ected by move mentof the master controller to its intermediate operating position 7), andthe actuation of the controller to its initial position a will merelyconnect themotors in series circuit relation with all of theaccelerating resistors.

Assuming that the, master reverser MR and the reversing switch RS aremoved to their corresponding forward running positions and that themaster controller MC is actuated to its final operating position 0, the

operation of the control system may be described as follows: Energy issupplied from one terminal 13-}- of the storage battery SB throughconductor 40, control, fingers 41 and 42, which are bridged by a contactmember 43 of the master controller, conductor 44, control fingers 45 and46, which are bridged by an interlocking contact member 47 of the masterreverser, conductor 48, fingers 49 and 50, which are bridged by acontact member 51 of the reversing switch RS, conductor 52, and theactuating coil of the switch l 1 to conductor 53, which is connected tothe opposite terminal of the battery SE. A second circuit is completedfrom conductor 52 through conductor 54, the actuating coil of the switchJ R, conductor 55, interlocking contact member 56, which occupies theposition shown when the switch J occupies its out position, conductor 57interlocking contact member 58 of the switch M in its out position, andconductors 59 and 53 to the negative battery terminal. The switches Mand JR are thus closed to connect the motors in series-circuit relation,

with all of the accelerating resistors across the supply circuit.

Substantially concurrently with the operation of the above-mentionedswitches, a circuit is established from an energized contact segment 67of the master controller through control finger 68, conductor 69, theenergizing coil of switch S, and conductor 57 back to the negativeconductor 53. Upon the closure of switch S, the oscillating rod 63 (Fig.4) is mechanically actuated to opcrate the electromagnetic device 64,which is associated with the switch RR in a manner hereinbeforedescribed. The closure of the switch RR actuates a rod 65 to operate theelectromagnetic device 66, which is associated with the switch R Theswitches RR and R are similarly actuated in progression, dependent uponthe particular adjustment of the corresponding electromagnetic devices.All of the resistor short-circuiting switches are then closed, and themotors are disposed in full series relation. It will be noted that theresistor short-circuiting switches which are dependent for theiractuation upon an electromagnetic device similar to that illustrated inFig. 5, severally serve to dispose their actuating coil 13 in a parallelcircuit with the movable con tact member of the respective switch uponclosure thereof (best shown in Fig. l) consequently, the current flowingthrough the coil is not of a suiiiciently high value to cause anyfurther operation of the electromagnetic device, and the switch,therefore,

finger 71 whence circuit is completed through conductor 72, theactuating coil of the switch J, control fingers 73 and 74, which arebridged by an interlocking contact member 7 5 when the switch J occupiesits open position, conductor 7 6, control fingers 7S and 7 9, which arebridged by interlocking contact member 80 when the switch R occupies itsclosed position, conductors 81 and 81 control fingers 82' and 88, whichare bridged by the contact member 58 of the switch M in its openposition, and conductor 59 to the negative conductor 53. After theswitch J is closed, the energizing circuit of its actuating coil istransferred to the conductor 84, which is connected with the conductor81 The closure of the switch J effects the deenergization of theactuating coil of the switch JR by the interruption of the coil circuitat the contact member 56. The switches RR to R inclusive, are thensuccessively and rapidly opened, in the manner hereinbefore described.It should be noted that the switch S and the associated resistor areexcluded from the circuit. by the opening of the switch JR. j

Also, upon the closure of the switch J, the mechanically-associatedoscillating rod 85 is actuated to operate the electromagnetic device 86,which is associated with the switch M as indicated in Fig. 4. Theclosure of the switch M closes the switch G by reason of theenergization of a circuit including conductor 54, the actuating coil ofthe switch, conductor 87, interlocking contact member 88 of the switch Rin its open position, conductor 89, control fingers 90 and 83, which arebridged by the contact member 58 of the switch M when the latteroccupies its closed position, as hereinbefore described; and conductor59 to the return circuit conductor 53. Upon the closure of the switch G,the energizing circuit of its actuating coil is transferred to controlfingers 91 and 92, which are bridged by an interlocking contact member93 of the switch G in its closed position, and conductor 94, to thefinger 90.

The closure of the switch M also opens the energizing coil circuit ofthe switch J at the contact member 58, thereby opening the switch Jpreferably just subsequent to the closure of the switch G. The switch Mis thus maintained closed by the action of a. rod 85, that is actuatedby the switch G, upon the electromagnetic device 86, before the rod 85is rendered inoperative by the opening of the switch J. The resistorshortcircuiting switches are opened before the closure of the switch G,however, thereby precluding the possibility of short-circuit across thesupply circuit through the switches M J and G.

The closure of the switch M also mechanically actuates the device 64,which is associated with the switch RR, similarly to the actuationthereof by the closure of the switch S, as hereinbefore described, andas indicated in Fig. 4. The successive closure of the remaining resistorshort-circuiting switches R RR and R is accomplished in the same manneras that hereinbefore set forth. The motors are thus connected in fullparallel relation.

I do not wish to be restricted to the specific circuit connections,arrangement of parts, or structural details herein set forth, as manymodifications thereof may be made within the spirit and scope of myinvention. I, therefore, desire that only such limitations shall beimposed as are indicated in the appended claims.

I claim as my invention:

1. In a system of control, the combination with a plurality of electricmotors, of means for automatically effecting series-parallel operationthereof, said means embodying a plurality of fluid-pressure operatedmotorcontrolling switches, a plurality of electromagnetic devices forrespectively delivering fluid pressure to certain of said switches underpredetermined conditions, and mechanical means operated upon the closureof certain switches for respectively actuating the electromagneticdevice associated with the next succeeding switch to close said switchwhen the motor current assumes a. predetermined value.

2. In a system of control, the combination with a plurality of electricmotors, of means for automatically effecting series-parallel operationthereof, said means com rising an auxiliary control circuit, a controler, a lurality of electromagnetic devices adapted to be connected incircuit with the motors, and a plurality of fluid-pressure operated,motor-controlling switches, certain of which are governed through saidcontroller from said control circuit, and others of which are dependentfor operation upon the mechanical actuation of the correspondingelectromagnetic device by the closure of a certain switch and upon thetraversal of a predetermined current through said corresponding device.

3. In a system of control, the combination with a main supply circuitand an electric motor supplied therefrom, of a plurality offluid-pressure operated motor-controlling switches, certain of which areelectrically governed and others of which are respectively dependent foroperation upon electrical means adapted for mechanical actuation byother switches under predetermined conditions.

4. In a system of control, the combination with a main supply circuitand an electric motor supplied therefrom, of an auxiliary supplycircuit, a plurality of fluid-pressure operated motor-controllingswitches, certain of which are electrically governed from said auxiliarysupply circuit and others of which are respectively dependent foroperation upon means mechanically actuated by the movement of otherswitches when the motor current assumes a predetermined value.

5. In a system of control, the combination with a main supply circuit,an electric motor supplied therefrom, and an auxiliary supply circuit,of a controller, a plurality of elec tro-magnetic devices adapted to beconnected in circuit with the motor, and a plurality of fluid-pressureoperated, mot0r-controlling switches, certain of which are governedthrough said controller from said supply circuit and others of which aredependent for operation upon the mechanical actuation of thecorresponding electromagnetic device by the closure of a certain switchand upon the traversal of a predetermined current through saidcorresponding device.

6. In a system of control, the combination with a main supply circuitand an electric motor supplied therefrom, of a controller, anauxiliarysupply circuit, a plurality of electromagnetically-operated,fluid-pressure controlling valves adapted to be connected in circuitwith the motor, and a plurality of fluid-pressure operated,motorcontrolling switches, certain of which are directly governedthrough said controller from said supply circuit and others of which areoperated upon the mechanical actuation of the corresponding valve by theclosure of a certain switch and upon the concurrent traversal of apredetermined relatively low motor current through said Valve.

7. In a system of control, the combination with an electric motor, of aplurality of motor-controlling, fluid-pressure governing switchingdevices including fluid-pressure operated members, one of which devicesis directly electrically governed and others of which are thereuponmechanically actuated successively, according to the value of motorcurrent, to admit fluid pressure to the corresponding fluid-pressureoperated member.

8. In a system of control, the combination with an electric motor, of aplurality of fluid-pressure operated motor-controlling switches, meansfor electrically governing one of said switches irrespective of motoroperation, and means dependent upon the value of motor current formechanically successively actuating a plurality of other switches.

9. A switching device comprising a plurality of cooperating stationaryand movable contact members, a fluid-pressure operated device foractuating the movable memher, and means dependent upon a predeterminedcurrent value and upon external mechanical actuation for admitting fluidpressure to said device.

10. A switching device comprising a plurality of cooperating stationaryand movable contact members, a fluid-pressure operated device foractuating the movable member, and electromagnetic means dependent uponexternal mechanical actuation for admitting fluid pressure to saiddevice when the electromagnetic force exerted by said means decreasesbelow a predetermined value.

11. A switching device comprising a plu rality of cooperating stationaryand movable contact members, a fluid-pressure oper ated device foractuating the movable memher, a valve for admitting fluid pressure tosaid device and normally biased to its closed position, adjustableelectromagnetic means tending to hold the valve closed, and externalmechanical means dependent upon the force exerted by saidelectromagnetic means for opening said valve to effect engagement ofsaid contact members.

In testimony whereof, I have hereunto subscribed my name this 25th dayof Au 1914.

HOWARD L. BEACH.

I Copies of this patent may be obtained for five cents each, byaddressing the Commissioner of Patents,

Washington, D. G.

